Due to extensive dust storms in Mars' southern hemisphere causing record atmospheric opacity levels, Opportunity is currently experiencing its lowest power levels to date. The tau measurement as of sol 1225 is 4.12, resulting in a mere 280 watt-hours of array energy. A tau measurement of 5.0 would result in approximately 150 watt-hours. If tau begins to approach 5.0, the team will have to begin deleting communications windows in order to conserve energy and keep from draining the batteries.

Sol 1223: On this sol, Opportunity used its microscopic imager, then retracted its robotic arm. This action was confirmed with the rover's navigation camera. The rover then closed the microscopic imager dust cover and confirmed this step with the navigation camera. Diagnostic testing on the arm stall was conducted.